U.S. Department of Justice

Office of Justice Programs

Bureau of Justice Statistics

BJS

Special Report

september 2013 ncj 242938

Requests for Police Assistance, 2011

Matthew Durose and Lynn Langton, Ph.D., BJS Statisticians

I

n 2011, an estimated 31.4 million U.S. residents age 16 

or older, or 13% of the population, requested assistance 

from the police at least once. About 93% of persons 

who requested police assistance thought the officers acted 

properly, 86% felt the police were helpful, and 85% were 

satisfied with the police response (figure 1). About 93% 

of persons who requested police assistance reported that 

they were just as likely or more likely to contact the police 

again for a similar problem.

The findings in this report are based on the Bureau 

of Justice Statistics’ (BJS) 2011 Police-Public Contact 

Survey (PPCS), a supplement to the National Crime 

Victimization Survey (NCVS), which collects information 

from a nationally representative sample of persons in U.S. 

households. The PPCS collects information on contact with 

police during a 12-month period. This report presents the 

characteristics and experiences of persons who contacted 

law enforcement for assistance in 2011, examining 

perceptions of officer behavior and response during these 

encounters. It details requests for police assistance to 

(1) report a crime, suspicious activity, or neighborhood 

disturbance; (2) report a noncrime emergency; and 

(3) seek help for a nonemergency or other reason.

Highlights

Among persons requesting assistance from the police in 2011:

 An estimated 1 in 8 U.S. residents age 16 or older, or 31.4 

million persons, requested assistance from police at least 

once, most commonly to report a crime, suspicious activity, 

or neighborhood disturbance. 

 The majority of persons who requested police assistance felt 

the officers acted properly (93%) and were helpful (86%).

 About 85% of persons who requested police assistance 

were satisfied with the police response. 

 No statistical differences were found between the 

percentage of Hispanics (86%), blacks (85%), and whites 

(83%) who reported a crime or neighborhood disturbance 

and felt the police were helpful.

 Most (93%) persons who requested police assistance felt 

the officers spent an appropriate amount of time with them 

during the contact.

 About 9 in 10 persons who requested police assistance 

reported that they were just as likely or more likely to 

contact the police again for a similar problem.

Figure 1

Perceptions of police behavior and response following 

requests for assistance, 2011

Note: Data based on the person’s most recent contact with police in 2011.

Percentages exclude 1.7% of respondents who did not know or report whether 

the police were helpful, 2.9% who did not know or report whether the police 

acted properly, and 0.8% who did not know or report whether they were satisfied 

with the police response. See appendix table 4 for standard errors.

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Police behavior and response

0 20 40 60 80 100

Satised with the 

police response

Police acted

properly

Police were

helpful

Percent of persons age 16 or older

86%

93%

85%
requests for police assistance, 2011 | september 2013 2

An estimated 1 in 8 persons requested police 

assistance in 2011

During 2011, an estimated 26% of the 241.4 million U.S. 

residents age 16 or older had one or more contacts with 

police, such as calling to report a crime, being stopped 

in a moving vehicle, or being approached by an officer 

in a public place (table 1). About 13% of the population 

requested assistance from the police at least once in 2011. 

For information on involuntary contacts with police that 

occurred during a traffic or street stop, see Police Behavior 

during Traffic and Street Stops, 2011, NCJ 242937, BJS web, 

September 2013.

The most common reason persons sought assistance from 

the police in 2011 was to report a crime, suspicious activity, 

or neighborhood disturbance (about 19.7 million persons 

or 8% of the population), followed by reporting a noncrime 

emergency (12.6 million or 5%), such as a medical issue 

or traffic accident. About 3.9 million persons, or 2%, 

sought help from the police for other reasons, such as 

having a problem with an animal, returning a lost item, or 

nonemergency matters (e.g., asking for directions.) 

In 2011, a similar percentage of females (13%) and males 

(13%) requested some type of assistance from the police 

(table 2). A greater percentage of non-Hispanic white 

persons (14%) than Hispanic persons (10%) contacted the 

police for assistance. A slightly larger percentage of white 

persons (14%) than black persons (12%) requested police 

assistance. In 2011, persons ages 25 to 44 contacted the 

police to request assistance at higher rates than younger 

persons (ages 16 to 24) and older persons (age 65 or older). 

The rates among persons ages 25 to 44 and 45 to 64 were not 

statistically different. 

A similar percentage of males (8%) and females (9%) 

contacted the police to report a crime or neighborhood 

disturbance in 2011. Across all races and Hispanic origin, 

American Indians and Alaska Natives (15%) and persons of 

two or more races (15%) had the highest rates of reporting 

crime or neighborhood disturbances to the police. No 

statistical difference was observed between the percentage 

of white (9%) and black (7%) persons reporting a crime or 

neighborhood disturbance to police in 2011.

Table 1

U.S. residents age 16 or older who had contact with police, 

by reason for contact, 2011

Reason for contact with police Number Percent

Total 62,937,000 26.1%

Requested assistance 31,405,000 13.0%

Reported crime/disturbance/suspicious 

 activity 19,737,000 8.2

Reported noncrime emergency 12,566,000 5.2

Other reasona 3,900,000 1.6

Stopped/approached by policeb 35,425,000 14.7%

Involved in a traffic accident reported to police 7,434,000 3.1%

Participated in an anti-crime program with police 3,490,000 1.4%

Note: Data based on the 241,404,000 U.S. residents age 16 or older in 2011. 

Numbers and percentages include persons who experienced contact with police 

anytime during 2011. Detail sums to more than total because some persons 

had more than one type of contact with police in 2011. Number of persons who 

requested police assistance rounded to nearest thousand. See appendix table 1 

for standard errors. 

aIncludes other reasons for approaching or seeking help from police, such as 

asking for directions, having a problem with an animal, or returning a lost item.

bIncludes persons who had involuntary contact that was initiated by the police 

such as being pulled over in a moving vehicle, being arrested for a crime, or 

being approached for some other reason (e.g., police were providing a service or 

conducting a criminal investigation).

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Table 2

U.S. residents age 16 or older who requested assistance 

from police, by reason for contact and demographic 

characteristics, 2011

Reason for police contact

Demographic 

characteristic Total

Reported crime/ 

disturbance/ 

suspicious 

activity

Reported 

noncrime 

emergency

Other 

reasona

Total 13.0% 8.2% 5.2% 1.6%

Sex

Male 12.5% 7.8% 5.0% 1.5%

Female 13.5 8.5 5.4 1.7

Race/Hispanic origin

Whiteb 13.9% 8.6% 5.7% 1.8%

Black/African

 Americanb 12.0 7.5 4.5 1.4

Hispanic/Latino 10.1 7.0 3.6 0.9

American Indian/

 Alaska Nativeb 17.0 15.2 4.8 ! 3.1!

Asian/Native

 Hawaiian/other 

 Pacific Islanderb 8.5 5.2 3.1 1.3

Two or more racesb 22.2 15.1 8.2 2.9

Age

16–17 5.5% 2.3% 2.8% 0.6% !

18–24 12.7 7.5 5.2 1.5

25–34 15.0 10.1 5.8 1.4

35–44 15.1 9.7 6.0 1.7

45–54 14.1 8.8 6.0 2.1

55–64 13.3 8.3 5.1 2.0

65 or older 9.1 5.5 3.4 1.2

Number requesting

 assistance 31,405,000 19,737,000 12,566,000 3,900,000

Note: Data based on the 241,404,000 U.S. residents age 16 or older in 2011. 

Numbers and percentages include persons who requested assistance from police 

anytime during 2011. Number of persons who requested assistance from police 

rounded to nearest thousand. See appendix table 2 for standard errors.

! Interpret with caution. Estimate based on 10 or fewer sample cases, or 

coefficient of variation is greater than 50%.

aIncludes other reasons for approaching or seeking help from police, such as 

asking for directions, having a problem with an animal, or returning a lost item.

bExcludes persons of Hispanic or Latino origin.

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.
requests for police assistance, 2011 | september 2013 3

About 6 in 10 requests for police assistance involved 

face-to-face contact with an officer

In 2011, persons who requested assistance from law 

enforcement were asked about the methods used to contact 

the police and whether the contact was face-to-face. Persons 

who reported more than one contact with police in 2011 were 

asked to describe the most recent contact. About 24.2 million 

persons reported that their most recent or only contact in 

2011 was to request assistance from the police (table 3). 

About 6 in 10 (62%) persons who requested police assistance 

in 2011 had face-to-face interaction with an officer during 

their most recent contact. Among persons who requested 

police assistance and had face-to-face contact with an officer, 

about 3 in 4 persons (75%) initiated the contact by telephone 

(not in table). The other 25% of contacts were initiated by 

the person approaching the police in public (e.g., the police 

station or on the street), the police coming to the person’s 

house, a third party (e.g., a company or another person 

contacting the police), or another method. 

The majority (93%) of persons who requested police 

assistance felt the officers acted properly 

Persons who requested assistance from the police (either 

in-person or not in-person) for any reason were asked if 

they felt police acted properly during the contact, were 

helpful, spent an appropriate amount of time with them, and 

improved the situation. In addition, persons were asked if 

they were satisfied with the police response and if they were 

likely to contact the police again for a similar problem. 

During 2011, the majority of persons who requested 

assistance from the police for any reason felt the responding 

officers acted properly (93%) and were helpful (86%) 

(table 4). About 85% of persons who had contact with 

police to request assistance were satisfied with how the 

police handled the situation. The percentage of persons who 

were satisfied with the police response was not statistically 

different among requests for assistance that involved 

face-to-face contact with an officer (85%) and contacts that 

were not in-person (84%) (not in table). 

While most people who requested police assistance 

believed the officers were helpful, a larger percentage of 

persons reporting noncrime emergencies (93%) than 

persons reporting crimes or neighborhood disturbances 

(84%) thought the police were helpful. Similarly, a larger 

percentage of persons reporting noncrime emergencies 

(91%) than persons reporting crimes or neighborhood 

disturbances (82%) were satisfied with the police response.

Table 3

Persons who requested police assistance who had face-to-face 

contact with an officer, by reason for most recent contact, 2011

Reason for most recent contact

Number 

requesting 

assistance

Percent who had face-to-face 

with police after requesting 

assistance

Total Yes No

Total 24,227,000 100% 62.1 37.9

Reported crime/disturbance/ 

 suspicious activity 14,523,000 100% 67.0 33.0

Reported noncrime emergency 6,477,000 100% 46.2 53.8

Other reason* 3,228,000 100% 72.1 27.9

Note: Percentages based on the 24.2 million persons who reported that 

their most recent contact in 2011 was to request assistance from the police. 

Percentages exclude less than 0.1% of respondents who did not report whether 

the contact was face-to-face. Number of persons who requested assistance from 

police rounded to nearest thousand. See appendix table 3 for standard errors.

*Includes other reasons for approaching or seeking help from police, such as 

asking for directions, having a problem with an animal, or returning a lost item. 

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Table 4

Perceptions of police behavior and response during contacts 

to request assistance, by reason for most recent contact and 

race/Hispanic origin of persons, 2011

Reason for most recent contact Alla Whiteb

Black/African 

Americanb Hispanic/ Latino

Police were helpful

 Total 86.4% 86.7% 83.2% 87.9%

Reported crime/disturbance/

 suspicious activity 84.0 83.5 85.0 86.0

Reported noncrime emergency 93.2 93.9 82.6 95.6

Other reasonc 83.9 85.5 75.1 81.5

Police acted properly

 Total 93.1% 93.5% 90.4% 92.8%

Reported crime/disturbance/

 suspicious activity 92.4 92.3 92.6 92.5

Reported noncrime emergency 95.6 96.3 88.1 96.0

Other reasonc 90.9 92.5 83.5 86.9

Satisfied with police response

 Total 84.7% 85.8% 80.1% 81.4%

Reported crime/disturbance/ 

 suspicious activity 82.0 82.7 80.5 79.0

Reported noncrime emergency 91.4 92.5 79.2 90.9

Other reasonc 83.6 85.4 80.0 73.9

Note: Data based on the person's most recent contact with police in 2011. 

Percentages exclude 1.7% of respondents who did not know or report whether 

the police were helpful, 2.9% who did not know or report whether the police 

acted properly, and 0.8% who did not know or report whether they were satisfied 

with the police response. See appendix table 4 for standard errors.

aIncludes estimates for persons identifying as white, black, Hispanic, American 

Indian, Alaska Native, Asian, Native Hawaiian, or other Pacific Islander, and 

persons of two or more races. Separate statistics on American Indians, Alaska 

Natives, Asians, Native Hawaiians, or other Pacific Islanders, and persons of two 

or more races are not shown due to too few sample cases to obtain reliable 

estimates.

bExcludes persons of Hispanic or Latino origin.

cIncludes other reasons for approaching or seeking help from police, such as 

asking for directions, having a problem with an animal, or returning a lost item. 

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.
requests for police assistance, 2011 | september 2013 4

Among persons reporting noncrime emergencies, Hispanics 

(96%) and whites (94%) were more likely than blacks (83%) to 

feel the police were helpful. Among persons reporting a crime 

or neighborhood disturbance in 2011, no statistical differences 

were found between the percentage of Hispanics (86%), blacks 

(85%), and whites (83%) who felt the police were helpful. 

While the large majority of white, black, and Hispanic 

persons who reported noncrime emergencies to law 

enforcement felt the officers provided a satisfactory 

response, blacks (79%) were less likely than whites (93%) 

and somewhat less likely than Hispanics (91%) to feel 

satisfied with the response. Among persons reporting a 

crime or neighborhood problem, a similar percentage of 

whites (83%), blacks (80%), and Hispanics (79%) were 

satisfied with the police response.

A similar percentage of males (86%) and females (86%) who 

requested assistance from the police felt the officers were 

helpful (table 5). No statistical differences were observed 

across age groups of persons who believed the police were 

helpful during requests for assistance.

Among persons who requested assistance from the police in 

2011, about 61% felt the police improved the situation, 21% 

felt the police did not improve the situation, and 18% were 

unable to say whether the situation did or did not improve 

(table 6). A larger percentage of persons reporting noncrime 

emergencies (70%) than persons reporting crimes or 

neighborhood disturbances (58%) felt the police improved 

the situation.

About 9 in 10 persons who requested police assistance 

felt the police spent an appropriate amount of time 

with them during the contact

Overall, most (93%) persons who requested police assistance 

in 2011 felt the officers spent an appropriate amount of time 

with them during the contact (table 7). An estimated 2% of 

persons felt the police spent too much time with them, and 

6% felt the police spent too little time with them. 

Table 5

Perceptions of police behavior and response during contacts 

to request assistance, by sex and age of person, 2011

Demographic characteristic

Police were 

helpful 

Police acted 

properly

Satisfied with 

police response

Total 86.4% 93.1% 84.7%

Sex

Male 86.5% 93.4% 84.8%

Female 86.4 92.8 84.6

Age

16–17 89.9% 94.7% 88.4%

18–24 87.1 94.3 81.5

25–34 85.0 91.0 82.9

35–44 87.4 93.6 85.2

45–54 85.4 92.9 84.4

55–64 86.4 93.4 84.8

65 or older 88.2 94.7 89.1

Note: Data based on the person’s most recent contact with police in 2011. 

Percentages exclude 1.7% of respondents who did not know or report whether 

the police were helpful, 2.9% who did not know or report whether the police 

acted properly, and 0.8% who did not know or report whether they were satisfied 

with the police response. See appendix table 5 for standard errors. 

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Table 6

Persons who felt police improved the situation during 

contacts to request assistance, by reason for most recent 

contact, 2011

Reason for most recent contact

Percent who felt the police improved 

the situation

Total Yes No Don’t know

Total 100% 61.3 20.9 17.8

Reported crime/disturbance/

 suspicious activity 100% 57.7 25.6 16.7

Reported noncrime emergency 100% 69.9 8.4 21.7

Other reason* 100% 60.3 25.3 14.4

Note: Data based on the person’s most recent contact with police in 2011. 

Percentages exclude 0.1% of respondents who did not report whether the police 

improved the situation. See appendix table 6 for standard errors.

*Includes other reasons for approaching or seeking help from police, such as 

asking for directions, having a problem with an animal, or returning a lost item.

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Table 7

Persons who felt police spent an appropriate amount of time 

with them after requesting assistance, by perceptions of 

police behavior and response, 2011

Police behavior 

and response

Percent who felt police spent an 

appropriate amount of time with them

Total Yes No, too much No, too little

Total 100% 92.9 1.5 5.6

Police were helpful 

Yes 100% 97.6 0.6 1.8

No 100% 60.0 8.1 31.8

Police acted properly

Yes 100% 97.4 0.8 1.8

No 100% 36.7 11.7 51.5

Satisfied with police response

Yes 100% 98.5 0.6 0.9

No 100% 59.3 7.0 33.8

Note: Data based on the person's most recent contact with police in 2011. 

Percentages exclude 3.5% of respondents who did not know or report whether 

the police spent an appropriate amount of time with them. See appendix table 7 

for standard errors.

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.
requests for police assistance, 2011 | september 2013 5

Perceptions about whether police spent an appropriate 

amount of time responding to requests for assistance 

were related to views about the behavior and response of 

police during the contact. Among persons who believed 

the police had not behaved properly, about 37% thought 

the police spent an appropriate amount of time with them. 

In comparison, among persons who felt the police acted 

properly, 97% felt the police spent an appropriate amount 

of time with them. Among persons who felt the police 

did not provide a satisfactory response during a request 

for assistance, about 59% believed the officers spent an 

appropriate amount of time with them, compared to about 

98% of persons who were satisfied with the police response.

About 9 in 10 persons who requested police assistance 

in 2011 stated they were just as likely or more likely to 

contact police again for a similar problem

The large majority of persons who requested police 

assistance to report a crime or neighborhood disturbance 

(93%) or a noncrime emergency (96%) stated they were 

just as likely or more likely to contact the police again 

for a similiar problem (table 8). In addition, the majority 

of persons reported being just as likely or more likely to 

contact the police again for a similar problem, even when 

the police were not helpful (65%), did not behave properly 

(53%), or did not provide a satisfactory response (66%). 

However, negative perceptions of police behavior were 

related to a lower likelihood of persons contacting the 

police in the future. For example, among persons requesting 

police assistance in 2011, about 47% of those who believed 

the police had not acted properly reported that they were 

less likely to contact the police again for a similar problem, 

compared to 4% of persons who felt the police behaved 

properly (table 9). 

Table 8

Persons who requested police assistance who reported how likely they were to contact police again for a similar problem, by 

reason for most recent contact, 2011

How likely to contact police again for a similar problem

Reason for most recent contact Total More likely to call Just as likely to call Less likely to call

Total 100% 33.9 59.2 6.9

Reported crime/disturbance/suspicious activity 100% 34.1 58.4 7.5

Reported noncrime emergency 100% 34.0 61.7 4.2

Other reason* 100% 33.0 57.5 9.5

Note: Data based on the person's most recent contact with police in 2011. Percentages exclude 1.8% of respondents who did not know or report how likely they were to 

contact the police again for a similar problem. See appendix table 8 for standard errors.

*Includes other reasons for approaching or seeking help from police, such as asking for directions, having a problem with an animal, or returning a lost item. 

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.

Table 9

Persons who requested police assistance who reported how likely they were to contact police again for a similar problem, by 

perceptions of police behavior and response, 2011

How likely to contact police again for a similar problem

Police behavior and response Total More likely to call Just as likely to call Less likely to call

Total 100% 33.9 59.2 6.9

Police were helpful 

Yes 100% 36.8 60.6 2.7

No 100% 16.3 48.8 34.9

Police acted properly

Yes 100% 36.0 60.4 3.6

No 100% 9.1 43.8 47.1

Satisfied with police response

Yes 100% 37.2 60.6 2.2

No 100% 16.2 50.1 33.7

Note: Data based on the person's most recent contact with police in 2011. Percentages exclude 1.7% of respondents who did not know or report whether the police were 

helpful, 2.9% who did not know or report whether the police acted properly, 0.8% who did not know or report whether they were satisfied with the police response, and 

1.8% of respondents who did not know or report how likely they were to contact the police again for a similar problem. See appendix table 9 for standard errors.

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.
requests for police assistance, 2011 | september 2013 6

Methodology

Data collection

The Police-Public Contact Survey (PPCS) is a supplement 

to the National Crime Victimization Survey (NCVS). The 

NCVS annually collects data on crimes reported and not 

reported to the police against persons age 12 or older from 

a nationally representative sample of U.S. households. The 

sample includes persons living in group quarters (such 

as dormitories, rooming houses, and religious group 

dwellings) and excludes persons living in military barracks 

and institutional settings (such as correctional or hospital 

facilities) and the homeless. (For more information, see the 

Survey Methodology in Criminal Victimization in the United 

States, 2008, NCJ 231173, BJS web, May 2011.)

Since 1999, the PPCS has been administered every 3 years 

at the end of the NCVS interview to persons age 16 or older 

within households sampled for the NCVS. Proxy responders 

and those who complete the NCVS interview in a language 

other than English were not eligible to receive the PPCS. 

The U.S. Census Bureau administered the 2011 PPCS 

questionnaire between July 1, 2011, and December 31, 2011, 

and processed the survey data. Respondents were provided 

a list of specific reasons for having contact with police and 

were asked if they had experienced any of those types of 

contacts during the prior 12 months. For example, persons 

interviewed in July 2011 were asked about contacts that 

occurred between August 2010 and July 2011. Persons who 

said they had a contact during 2011 were asked to describe 

the nature of the contact, and those who had more than one 

contact were asked about only their most recent contact 

during the period. To simplify the discussion of the findings, 

this report describes all contacts reported during the 12 

months prior to the interviews as 2011 contacts. 

PPCS nonrespondents consisted of persons whose household 

did not respond to the NCVS (NCVS household nonresponse), 

persons within an interviewed NCVS household who did 

not respond to the NCVS (NCVS person nonresponse), and 

persons who responded to the NCVS but did not complete 

the PPCS (PPCS person nonresponse). The NCVS household 

response rate was 89% and the person response rate was 

88%. In 2011, PPCS interviews were obtained from 49,246 of 

the 62,280 individuals age 16 or older in the NCVS sample 

(79%). A total of 13,034 nonrespondents were excluded from 

the 2011 PPCS as noninterviews or as proxy interviews. 

Noninterviews (10,907) included respondents who were not 

available for the interview, those who refused to participate, 

and non-English-speaking respondents. (Unlike the NCVS 

interviews, PPCS interviews were conducted only in English.) 

The remaining 2,127 were proxy interviews representing 

household members who were unable to participate for 

physical, mental, or other reasons. 

To produce national estimates on police-public contacts, 

sample weights were applied to the survey data so that the 

respondents represented the entire population, including 

the nonrespondents. After adjustment for nonresponse, the 

sample cases in 2011 were weighted to produce a national 

population estimate of 241,404,142 persons age 16 or older.

Despite the nonresponse adjustments, low overall response 

rates and response rates to particular survey items can still 

increase variance in these estimates and produce bias when 

the nonrespondents have characteristics that differ from the 

respondents. The Office of Management and Budget guidelines 

require a nonresponse bias study when the overall response 

rate is below 80%. The Bureau of Justice Statistics (BJS) and the 

Census Bureau compared the distributions of respondents as 

well as nonrespondents and nonresponse estimates for various 

household and demographic characteristics, and examined 

their impact on the national estimates produced for the 2011 

PPCS. The study looked at household-level and person-level 

response rates and found some evidence of bias in the rates 

among blacks and persons of Hispanic origin. Blacks accounted 

for 12% of the U.S. population in 2011 but about 11% of PPCS 

respondents after weighting adjustments. Hispanics accounted 

for 14% of the U.S. population but about 12% of the PPCS 

respondents after weighting adjustments. Because the largest 

bias in person nonresponse was observed in the Hispanic 

origin characteristics, future iterations of the PPCS will address 

this issue by administering the survey in languages other 

than English and including Hispanic origin as a factor in the 

noninterview adjustment. Item nonresponse statistics were 

also computed for key survey questions from the PPCS, and no 

evidence of bias was found during the analysis.

Changes to the 2011 PPCS

Since its inception in 1999, the PPCS has captured 

information about in-person (i.e., face-to-face) contacts 

between police and the public. Telephone contacts were 

previously not included. The survey has also excluded 

face-to-face interactions in which persons approached an 

officer or an officer initiated contact with them in a social 

setting or because their work brought them into regular 

contact. In March of 2010, BJS hosted a series of meetings 

with subject-matter experts in the area of policing and police 

legitimacy to initiate discussion and work on substantive 

changes to the PPCS questionnaire. In 2011, based in part on 

these meetings, the PPCS was revised to expand the scope of 

the survey and to better capture contacts with police. 

First, to determine if contact occurred and to enhance 

individuals’ recollections about their interactions with 

police over a 12-month period, BJS implemented new 

screening procedures in the 2011 PPCS that describe a 

broad range of situations known to bring people in contact 

with police. Second, the scope of the PPCS was expanded 

to collect information about interactions that people had 
requests for police assistance, 2011 | september 2013 7

with the police that did not result in a face-to-face contact 

(e.g., reporting a crime to the police by phone or email). 

Additionally, a new set of questions was added to the 

instrument to collect detailed information about requests 

for police assistance (e.g., reporting a crime or noncrime 

emergency) and contacts in which the police stopped 

someone in a public place or on the street but not in a motor 

vehicle (street stops).

The effects of these revisions, which included adding new 

questions and reordering existing questions, were significant 

when compared to the 2008 version of the questionnaire. To 

assess the impact of the survey redesign on trends in rates 

and types of contact, BJS administered a split-sample design 

in which a subset of the sample was interviewed using 

the 2008 version of the questionnaire, and the remaining 

sample was interviewed using the 2011 version. Based on 

the evaluation, it was determined that a 15/85 split would 

provide sufficient power to measure a 15% change in 

contact rate. In other words, about 85% of the 2011 sample 

was randomly assigned the revised questionnaire and the 

other 15% received the questionnaire designed for the 

2008 survey. The Census Bureau completed interviews for 

41,408 (79%) of the 52,529 persons who received the revised 

questionnaire. 

The findings in this report are based on data collected from the 

revised questionnaire. An evaluation of the impact of the changes 

to the 2011 PPCS instrument on trends in contacts between 

the police and the public is underway, and the results of that 

assessment will be made available through the BJS website.

Standard error computations 

When national estimates are derived from a sample, as is the 

case with the PPCS, caution must be taken when comparing 

one estimate to another estimate. Although one estimate 

may be larger than another, estimates based on a sample 

have some degree of sampling error. The sampling error 

of an estimate depends on several factors, including the 

amount of variation in the responses, the size of the sample, 

and the size of the subgroup for which the estimate is 

computed. When the sampling error around the estimates is 

taken into consideration, the estimates that appear different 

may, in fact, not be statistically different.

One measure of the sampling error associated with an 

estimate is the standard error. The standard error can vary 

from one estimate to the next. In general, for a given metric, 

an estimate with a smaller standard error provides a more 

reliable approximation of the true value than an estimate 

with a larger standard error. Estimates with relatively large 

standard errors are associated with less precision and 

reliability and should be interpreted with caution.

In order to generate standard errors around estimates 

from the PPCS, the Census Bureau produces generalized 

variance function (GVF) parameters for BJS. The GVFs take 

into account aspects of the NCVS complex sample design 

and represent the curve fitted to a selection of individual 

standard errors based on the Jackknife Repeated Replication 

technique. The GVF parameters were used to generate 

standard errors for each point estimate (i.e., numbers or 

percentages) in the report.

In this report, BJS conducted tests to determine whether 

differences in estimated numbers and percentages were 

statistically significant once sampling error was taken into 

account. Using statistical programs developed specifically 

for the NCVS, all comparisons in the text were tested for 

significance. The primary test procedure used was Student’s 

t-statistic, which tests the difference between two sample 

estimates. To ensure that the observed differences between 

estimates were larger than might be expected due to 

sampling variation, the significance level was set at the 95% 

confidence level.

Police–Public Contact Survey questions pertaining 

to perceptions of police behavior and response 

following requests for assistance

Police behavior

Q. Looking back on this contact, do you feel the police 

behaved properly?

Q. Were the police helpful?

Police response

Q. Were you satisfied with the police response during your 

most recent contact?

Q. Did the situation improve after you contacted the police?

Amount of time police spent with the person 

during contact

Q. Do you believe the police spent an appropriate amount of 

time with you?

Likelihood of contacting the police again for a 

similar problem

Q. Would you be more likely, less likely, or just as likely to 

contact the police in the future for a similar problem?
requests for police assistance, 2011 | september 2013 8

Data users can use the estimates and the standard errors of 

the estimates provided in this report to generate a confidence 

interval around the estimate as a measure of the margin of 

error. The following example illustrates how standard errors 

can be used to generate confidence intervals:

According to the PPCS, an estimated 13% of persons 

age 16 or older requested assistance from the police in 

2011 (see table 1). Using the GVFs, BJS determined that 

the estimate has a standard error of 0.5 (see appendix 

table 1). A confidence interval around the estimate 

was generated by multiplying the standard error by 

±1.96 (the t-score of a normal, two-tailed distribution 

that excludes 2.5% at either end of the distribution). 

Thus, the confidence interval around the estimate is 

13% ± (0.5 X 1.96). In other words, if different samples 

using the same procedures were taken from the U.S. 

population in 2011, 95% of the time the percentage of 

persons age 16 or older who requested police assistance 

would be between 12% and 14%. 

In this report, BJS also calculated a coefficient of variation 

(CV) for all estimates, representing the ratio of the standard 

error to the estimate. CVs provide a measure of reliability 

and a means to compare the precision of estimates across 

measures with differing levels or metrics. In cases where the 

CV was greater than 50%, or the unweighted sample had 

10 or fewer cases, the estimate was noted with a “!” symbol 

(interpret data with caution; estimate is based on 10 or fewer 

sample cases, or the coefficient of variation exceeds 50%).

Many of the variables examined in this report may be related 

to one another and to other variables not included in the 

analyses. Complex relationships among variables were not 

fully explored in this report and warrant more extensive 

analysis. Readers are cautioned not to draw causal inferences 

based on the results presented.
requests for police assistance, 2011 | september 2013 9

Appendix table 1

Standard errors for table 1: U.S. residents age 16 or older 

who had contact with police, by reason for contact, 2011

Reason for contact with police Number Percent

Total 1,581,523 0.7%

Requested assistance 1,088,977 0.5%

Reported crime/disturbance/suspicious activity 822,688 0.3

Reported noncrime emergency 618,878 0.3

Other reason 289,181 0.1

Stopped/approached by police 1,167,506 0.5%

Involved in a traffic accident reported to police 440,856 0.2%

Participated in an anti-crime program with police 268,884 0.1%

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Appendix table 2

Standard errors for table 2: U.S. residents age 16 or older who requested assistance from police, by reason for contact and 

demographic characteristics, 2011

Reason for police contact

Demographic characteristic Total

Reported crime/disturbance/ 

suspicious activity

Reported noncrime 

emergency Other reason

Total 0.5% 0.3% 0.3% 0.1%

Sex

Male 0.5% 0.4% 0.3% 0.1%

Female 0.6 0.4 0.3 0.2

Race/Hispanic origin

White 0.5% 0.4% 0.3% 0.1%

Black/African American 0.8 0.6 0.5 0.2

Hispanic/Latino 0.7 0.6 0.4 0.2

American Indian/Alaska Native 3.4 3.2 1.8! 1.4 !

Asian/Native Hawaiian/other Pacific Islander 0.9 0.7 0.5 0.3

Two or more races 2.7 2.2 1.6 0.9

Age

16–17 0.8% 0.5% 0.6% 0.2% !

18–24 0.8 0.6 0.5 0.2

25–34 0.8 0.7 0.5 0.2

35–44 0.8 0.7 0.5 0.2

45–54 0.8 0.6 0.5 0.3

55–64 0.8 0.6 0.5 0.3

65 or older 0.6 0.5 0.3 0.2

Number requesting assistance 1,088,977 822,688 618,878 289,181

! Interpret with caution. Estimate based on 10 or fewer sample cases, or coefficient of variation is greater than 50%.

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.
requests for police assistance, 2011 | september 2013 10

Appendix table 3

Standard errors for table 3: Persons who requested police assistance who had 

face-to-face contact with an officer, by reason for most recent contact, 2011

Number requesting 

assistance

Percent who had face-to-face with 

police after requesting assistance

Reason for most recent contact Yes No

 Total 932,827 1.6% 1.5%

Reported crime/disturbance/suspicious activity 678,514 1.8 1.7

Reported noncrime emergency 402,977 2.4 2.4

Other reason 255,515 2.9 2.7

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.

Appendix table 4

Standard errors for table 4: Perceptions of police behavior and response during contacts to request assistance, by reason for 

mosr recent contact and race/Hispanic origin of persons, 2011

Reason for most recent contact All White Black/African American Hispanic/Latino

Police were helpful

Total 1.2% 1.3% 2.7% 2.4%

Reported crime/disturbance/suspicious activity 1.4 1.6 3.1 2.9

Reported noncrime emergency 1.3 1.3 4.9 2.6

Other reason 2.4 2.5 7.3 7.1

Police acted properly

Total 0.9% 1.0% 1.5% 1.7%

Reported crime/disturbance/suspicious activity 1.0 1.2 1.5 1.9

Reported noncrime emergency 1.5 1.7 4.3 3.3

Other reason 2.1 2.2 4.7 6.4

Satisfied with police response

Total 1.2% 1.3% 2.9% 2.8%

Reported crime/disturbance/suspicious activity 1.5 1.6 3.4 3.4

Reported noncrime emergency 1.5 1.5 5.2 3.7

Other reason 2.4 2.5 6.8 8.1

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.

Appendix table 5

Standard errors for table 5: Perceptions of police behavior and response during contacts to request 

assistance, by sex and age of person, 2011

Demographic characteristic Police were helpful Police acted properly Satisfied with police response

Total 1.2% 0.9% 1.2%

Sex

Male 1.5% 1.1% 1.5%

Female 1.4 1.1 1.5

Age

16–17 5.8% 4.3% 6.0%

18–24 2.5 1.8 2.9

25–34 2.0 1.6 2.1

35–44 1.9 1.4 2.0

45–54 2.0 1.5 2.0

55–64 2.1 1.5 2.2

65 or older 2.2 1.5 2.1

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.
requests for police assistance, 2011 | september 2013 11

Appendix table 6

Standard errors for table 6: Persons who felt police improved 

the situation during contacts to request assistance, by 

reason for most recent contact, 2011

Percent who felt the police 

improved the situation

Reason for most recent contact Yes No Don’t know

Total 1.6% 1.2% 1.1%

Reported crime/disturbance/

 suspicious activity 1.9 1.5 1.2

Reported noncrime emergency 2.3 1.1 1.9

Other reason 3.1 2.6 2.0

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Appendix table 7

Standard errors for table 7: Persons who felt police spent 

an appropriate amount of time with them after requesting 

assistance, by perceptions of police behavior and response, 

2011

Percent who felt police spent an 

appropriate amount of time with them

Police behavior and response Yes No, too much No, too little

Total 0.9% 0.3% 0.6%

Police were helpful 

Yes 0.6% 0.2% 0.3%

No 3.2 1.5 2.9

Police acted properly

Yes 0.6% 0.2% 0.3%

No 4.0 2.5 4.2

Satisfied with police response

Yes 0.4% 0.2% 0.2%

No 3.1 1.3 2.8

Source: Bureau of Justice Statistics, National Crime Victimization Survey, 

Police-Public Contact Survey, 2011.

Appendix table 8

Standard errors for table 8: Persons who requested police assistance who reported how likely they were to contact police 

again for a similar problem, by reason for most recent contact, 2011

How likely to contact police again for a similar problem

Reason for most recent contact More likely to call Just as likely to call Less likely to call

Total 1.4% 1.6% 0.6%

Reported crime/disturbance/suspicious activity 1.7 1.9 0.8

Reported noncrime emergency 2.2 2.4 0.8

Other reason 2.9 3.1 1.6

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.

Appendix table 9

Standard errors for table 9: Persons who requested police assistance who reported how likely they were to contact police 

again for a similar problem, by perceptions of police behavior and response, 2011

How likely to contact police again for a similar problem

Police behavior and response More likely to call Just as likely to call Less likely to call

Total 1.4% 1.6% 0.6%

Police were helpful 

Yes 1.6% 1.7% 0.4%

No 2.1 3.2 3.0

Police acted properly

Yes 1.5% 1.6% 0.4%

No 2.1 4.0 4.1

Satisfied with police response

Yes 1.6% 1.7% 0.3%

No 2.0 3.0 2.8

Source: Bureau of Justice Statistics, National Crime Victimization Survey, Police-Public Contact Survey, 2011.
Office of Justice Programs

Innovation • Partnerships • Safer Neighborhoods

www.ojp.usdoj.gov

The Bureau of Justice Statistics, located in the Office of Justice Programs, U.S. 

Department of Justice, collects, analyses, and disseminates statistical information on 

crime, criminal offenders, victims of crime, and the operation of justice systems at all 

levels of government. William J. Sabol is acting director.

This report was written by Matthew Durose and Lynn Langton. Lynn Langton 

verified the report.

Morgan Young edited the report. Tina Dorsey and Morgan Young produced the report.

September 2013, NCJ 242938